Now we want to try our final render. (it´snot the name of the render). For this I´ve built a very easy object, a pyramide with spheres. And on the top I´ve used the name of my great father in law, because it´s in his garden.

As you can see, I´ve used a plane for the ground. And I´ve positioned the plane, that it matches to the real ground of the bg image.
Why we use this plane ? Well, we want that our skylight will produce a shadow on the ground, and that´s the reason for.
Important is to know, that the plane should be a matte shadow. That means, that we want that the plane will receive shadows, and also that it will bounces back some rays. Okay, the theory makes sense, but how does it look like in the praxis ?
When you created your plane, select it, right mouse click and choose the Vray Properties. The following dialog will open:

We want to have the plane as matte shadow, so we activate this option. And of course we want to have our shadows, so we click this too.
Our next step is to get sure, that our plane will not have any reflection or refraction. If you wouldn´t deactivate that, every single 3d object would reflect the material from the ground. And in our case we don´t want to have it.

Notice: The light is bouncing back from the plane, so it makes sense to choose a grey color for your plane. With the grey color you can choose the brightness of this light. White would bounce 100% back and black would bring you a very dark result. I recommend to make different tests, and get sure that you know which settings will work best for you.
I think it´s very important to know about these settings. Now it´s your choice, which materials you use for your render. In my case, I´ve used a VrayMtl. I´ve loaded a bitmap texture into my difuse channel, and the same I´ve used monochrom as bump map. In the reflection channel I´ve used a Falloff-Map, from black to grey. Glossy 0.65 and the Index of Reflection (IOR) I set to 1.456.
All other parameters are the defautl settings from the VrayMtl.
Here you can see the final render.

Okay, keep in mind, that you want to make some changes after your rendering process. For that you want to have Alpha, Shadow, BG, Depth Map, GI, etc. With theses different passes you can make a lot of changes in Photoshop or even any other graphic programm.

You also can save every single image / pass on your harddisk, just use the G-Buffer. Okay, now you have made all your preperation in 3d.
Which images you want to export directly, you can choose in the G-Buffer.
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